1. Field of the Invention
The invention relates to sound deadening devices for window mechanisms.
2. Description of the Related Art
Rattling window balance springs are an annoying side effect of using current spring balance mechanisms. While the method of using a spring device to replace sash cords and counterweights is a significant improvement in window construction, a a window that rattles whenever a truck passes, a door slams or when the window is closed or opened rapidly may cause many homeowners to question the quality of such windows. Window manufacturers have been trying for years to develop a cost effective way to eliminate this aberration for years with only limited success.
Various coatings have been tried on the balance springs. U.S. Pat. No. 4,854,558, issued to Newton on Aug. 8, 1989, discloses a hot melt adhesive that is claimed stops rattling when applied to the window spring. This method requires a substantial increase in cost and can also present environmental problems for the factory in installing such coatings.
U.S. Pat. No. 4,540,070, issued to Yonovich on Sep. 10, 1985, discloses a plastic device that is attached to the window balance spring that keeps the spring from rattling against the walls of the spring cover. While this device solves the problems associated with trying to coat the balance spring, the apparatus must be applied by hand which increases the manufacturing costs of the window. As it is made from plastic, the fins that come into contact with the spring cover are subject to repeated flexing and, therefore, subject to fatigue failure from window opening and closing cycles.
A cost effective window spring damping apparatus that can be machine installed during the normal window manufacturing process is not found in the prior art.